Watebeboof broofiltg material ob the like aots pkocess of makibtg same



our rans an JAMES P. ELLIOTT, 0E OAK PARK, ILLLNOIS;

we I

ll,3@5,8ll. Specification of Letters Patent.

330 Drawing.

To all whom it may concern:

l 3e it known that 1, JAMES P. ELLIOTT, a citizen of the United States, residing at Oak Park, county ofCook, State of Illinois, have lnvented a certain new and useful Improvement in Waterproof Boo Materials or the like and Processes of Ma '11 Same, an declare the followin to be a full, clear," and exactdescription Q the same, such as will enable others skilled in the art pertains to make and use the same.

The material universally employed for making fibrous waterproof sheet roofing material is a low grade felt which, because of its comparative tenacity and capacity for absorbing melted asphalts or tars so as to become saturated with the same, has. heretofore encountered no successful competition from other materials, even though the felt, particularl at the present time, is very expensive. ubstitutes have been proposed and tried, but they have either lacked tenacity or capacity to absorb the waterproofin materials or have been of such a nature diet the cost to manufacture them would be greater than that of the ordinary felt roofing.

My invention has for its object to produce a substitute for felt roofing and the like which shall possessall of the desirable properties of the latter and at the same time be less expensive.

The manufacturer of the roofing usually buys the sheet felt and treats itto render it waterproof and, viewed in one of its aspects, my invention may be said to have for its object to produce a process of makinfixa water'proof fiber substitute for felt roo g and the like which will permit the manufacturer of roofing to emplo the same process of finishin raw sheets t at he has heretofore employ in waterproofing and finishing felt sheets. I

One of the materials that has often been tried as a substitute for the felt is wood pulp which is cheap and possesses suflicient strength; but wood pulp oes not readily absorb the usual waterproofing materials and efiorts to emplo it asa roofing material have therefore n unsuccessful. It has therefore long been reco ized that .wood pulp is the natural-substitute for felt provided it can be waterproofed thoroughly and its aspects my invention maybe regarded as having for its object to produce asimple to which it, I

ROOF ROOFING- MA'REREEAL OR THE LIKE PRQGESS 0F SAME;

- Patented May 2?, li ht Application filed march 11; 1916. Serial no. sense.

process of treating wood pulp so as totransorm it into a comparatively cheap and eflicient waterproof. material.

Just as it is desirable'to preserve the practices by which the felt is now being treated to render it waterproof, so as not to make it dnecessary. to reorganize or wholly remodel an existing factory, so also is it desirable that there be no interference with the ordinary processes by which wood pulp is produced; and, therefore, viewed in one of its aspects, my invention may be said to have for its object to produce a simple and novel process of manufacturing a waterproofed wood pulp which does not require any change in the process of or machinery for, producing ordinary wood pulp. I

In accordance with my invention ll prepare in dry powdery form a waterproofing material havl an' asphalt base or, in fact, of any composition which will answer purpose, and mix this with the wet wood pulp at any suitable stage in the process of manufacturin the latter, preferably inthe mixer just be ore the pulp is rolled out or pressed into sheets. The wood pulp sheets are therefore filled with finely divided, uniformly distributed particles of waterproofing material. These sheets are then treated in exactly the same way as felt is now treated, namely they are immersed in hot waterproofing material which coats the surface and enters into the body of the sheets to a reater or less extent and, because the bath is ot, the fine particles of waterproofing material existing in the sheets are caused to meltand become fluid and thus form. an effective seal throu which moisture cannot pass.

It will be seen that the addition of the dry powdery waterproofing material to the wood pulp does not interfere with the usual process of making the wood pulp sheets because the operation is exactly the same as if a coloring pigment or other material were added to the pulp in the process of making ord1- nary pulp. It will also be seen that the process of manufacturing the waterproof material from the wood pulp is the same as that heretofore pract'sed in connection with Waterproofing felt. Consequently I have devised a processby means of which it is posfor the ordinary waterproofed felt at a we much less .than'that of the latter and withthe y at not too great a cost. Viewed in one of sible to obtaina very satisfactory substitute.

out making it necessaryto disturb existing v plants or processes in order to adapt them sion of the prepared wo for the change of material.

It will, of course be understood that some of the advantages of my invention or dis coverymay be obtained by simply subjectin the prepared wood or straw ulp to a su cient degree of heatto melt t e waterproofing material contained therein although the product so produced will of course not'be the same as that resultin from the immer- 0d pulp in a hot bath of waterproofing material.

In. order to insure that the particles of waterproofing material contained in the wood pulp ,shallbe liquefied in the hot bath, it is preferable that the dry powdered waterproofing material that is employed be such that it will melt at a lower temperature than that constituting the bath. It is well known to those skilled in the art that the usual waterproofing materials may be made to melt atany deslredpoint within a comparatively wide range of temperatures and therefore no detailed explanation of how this is accomplished is necessary. It will be seen that by having in the pulp a material which will melt at a temperature considerably below that of the bath, very little skill is required to insure that the pulp will remain in the bath long enough to cause the temperature in every portion of the body-of pulp to become higher than that at w 'ch the waterproofing material will liquefymain purpose of my invention is to make possible the economical waterproofing of materials that heretofore could not be waterproofed successfully. Some of the advantages of the invention will of course be obtamed by using only some of the features thereof. Thus, for example, the powdered waterproofing material may be mixed with the pulp out of which the sheets of felt roofing material are now made; thus greatly shortening the-waterproofing process through which the felt must afterward be passed in order to transform it into roofing materiah Or, just as in the case of wood or straw pulp, a more or less complete waterproofing may be obtained by simply subjecting the felt made out of the treated pulp to a sufiicie'nt degree of heat .to melt the contained waterproofing material and cause it to flow. v

I claim: I

1. The process of manufacturing 'waterproofed roofing material which consists in mixing with amass of pulp small particles of waterproofing material, working the pulp intothe form of a sheet-in the usual way, and then subjecting the sheet "to a hot bath of liquefied waterproofing material in the manner in which ordinary felt roofing is commonly treated to waterproof it.

2. The method of producing waterproof sheet roofing which consists in incorporating in the sheet small particles of water- 3. The process of producing a 'waterproofed sheet roofing material which consists in making a sheet out of pul in the usual way with the addition of sma l particles of waterproofing material to the pulp at any convenient point in the process of making the sheet, and then immersing the sheet in a hot'liquefied waterproofing bath in the manner now employed for \waterproofing ordinary felt roofing material.

, 4. The process of producing a waterproofed body or sheet which consists in making it of pulp having small particles of waterproofing material distributed throughout the mass thereof and then immersing it in a hot bath of liquid waterproofing material.

= 5. The process of producing a waterproofed body or sheet which consists in making it of pulp havin small particles of Waterproofing material dlstributed throughout the mass of the same, and then subjecting it to a hot bath of liquefied wate roofing material whose melting point is igher 6. The process of producing fibrous waterproof sheet roofing material which It will of course be understood that theconsists in forming a sheet out of pulp in the usual way and, in the process of formation of the sheet without the addition of heat; adding finely divided waterproofing material to the pul and. then immersing the sheet in a hot ath to melt the waterproofing material.

7. The process of producin fibrous same time produce a waterproof coating on the exterior of the sheet.

8. The process of producing a waterproofed body or sheet which consists in r making it of pulp havin small particles of waterproofing material dlstributed' throughout the mass of the same, and then subjecting it to a hot bath of liquefied water roofing material whose temperature is ighe'rthan the melting point of the first mentioned waterproofing material.

9. The process of producing a waterproofed body or sheet which consists in intimately mixing wet pulp with finely-divided- 115 proofing material in the sheet and at the I asphalt, working the wet mixtureinto the desired shape, and then subjecting it to a hot bath of liquefied waterproofing material whose temperature is higher than the melting point of the said asphalt.

10. The (process of'producing a water- I y or sheet Which consists in intiproofed b o mately mlXlllg wet pulp with finely-divided 11. The process of producing fibrous.

waterproof sheet roofing material "which consists in forming a sheet out of pulp in the usual way and, in the process of forma tion of the sheet without the addition of heat, adding finely-divided asphalt to the pulp; and then immersing the sheet in a hot bath to melt the asphalt.

12. The process of producing a water- 4 proofedbody or sheet which consists in intimately mixing wet pulp and finely-divided asphalt, shaping the wet ulp while the asphalt still remains in. its nelydivided state and without changing it from such finelydivided state, and then simultaneously coating the body or sheet and melting the asphalt content thereof. 7

13. As an article of manufacture, a sheet of flexible and porous unsaturated building felt consistin 'of waterproofing material inv comminuted orm and other material.

14. As an article of manufacture, a sheet 36 of flexible and porous unsaturated building felt consisting of fusible waterproof mate rial in comminuted form and other material. 15. As an article of nianufacture,-a sheet of flexible and porous unsaturated building 40 felt' comprising a waterproofing material in comminuted form and paper stock material.

16. Asan' article of manufacture, a sheet of flexible and'porous unsaturated building felt comprising asphalt in comminuted form and a fibrous. material.

-17. As an article of manufacture w sheet of flexible and porous unsaturated building felt consisting of fusible waterproofing material in comminuted form and a fibrous maso terial.

18. The process of producing fibrous 1 waterproof sheet building felt which consists in forming a flexible-porous sheet out of comminuted fusible waterproofing material mixed with a fibrous material, and

theh ap'plying heat to the-sheet in order to melt the waterproofing material.

19. The process of producing fibrous waterproof sheet building felt which con- 0 sists in forming-a flexible porousv sheet out of comminuted asphalt mixed with a fibrous material, and then applyin heat to the sheet in order to melt the aspha t.

In testimony-whereof, I this speci- 5 fication.

'JS- r. ELLIOTT. 

